The principal objective is to develop information on the effects of soy protein and a low fat, high fiber diet on prostatic tissue cytokinetics and reproductive hormone secretion in men with localized prostate cancer. This information may provide new directions for the prevention and treatment of prostate cancer. In the proposed CRC studies, men w/ localized prostate cancer will be studied before radical prostectomy to determine the degree to which hormonal secretion of the intact prostate tumor, & peripheral hormone metabolism.